I need a single handle that uses oly plates and is 200+ pounds. Thank you.
I somehow doubt you want a 200lb dumbbell.
But I got a cheapo set of adjustable "Gold's Gym" DBs and an EZ curl bar from Walmart for $30. The DBs can handle 175 no issue. It helps to use a ton of 25s rather than 45s for ROM.
ProWristStraps.com has one that holds 500+ (or so they say). Probably overkill, and it's like $300, so that wouldn't be my first choice. I made one that held about 280 but I had to trim it down because it was a little too long. Holds about 220-240 now. Depends on what size clamps I use.